Nonradioactive Quantification of Low ... - Clinical Chemistry

3 downloads 0 Views 508KB Size Report
Mosca,1 Sara Calmi, Patrizia. Do Leonardis,. Clara Todaro,. Guglielmo. Zuliani,2 Mauro Buscaglia,3 and Angelo Cant#{224}-RaJnoldi4. The usual methods forĀ ...
CLIN.CHEM.38/9, 1906-1908 (1992)

Nonradioactive Quantification of Low Concentrations of Hemoglobin A by HPLC for Midtrimester Prenatal Diagnosis of J3-Thalassemia Silvana Tedeschi, Andrea Mosca,1 Sara Calmi, Patrizia Zuliani,2 Mauro Buscaglia,3 and Angelo Cant#{224}-RaJnoldi4

Rita Malavacca,

usual methods for prenatal diagnosis of /3-thaiassemia and other hemoglobinopathies by assay of fetal blood erythrocytes are either complex (analysis of globin chains synthesis by carboxymethylcellulose chromatography) or only semiquantitative[isoelectric focusing of hemoglobin (Hb)]. To further simplify the diagnostic procedure and to obtain quantitative data, we measured the small concentrations of Hb A in fetal erythrocytes by using a high-pressure liquid chromatography (HPLC) instrument (DIAMAT-TM; Bio-Rad) equipped with the new column proposed for measuring Hb A2. We analyzed 212 uncontaminated fetal blood samples obtained by cordocentesis between the 18th and 22nd weeks of pregnancy, usingthe HPLC procedure, and compared the resultswith those obtained by the above-named methods. The Hb A values obtained ranged between 0% and 8.5%; they were 1.8% in 44 fetuses affected by homozygous /3-thalassemia and >2.5% in 168 unaffected fetuses. The method was simple, rapid, and reproducible (CV 3.2%) and there was good correlation between Hb A concentrationsdetermined by HPLC and the fly ratio determined by carboxymethylcellulose chromatography (r = 0.7687; P